Herbicidal n&#39;-aryl-n-chlorocycloalkylthio ureas

ABSTRACT

COMPOUND OF THE FORMULA   R-N(-R1)-CO-N(-R2)-S-R2   WHEREIN R AND R1 ARE HYDROGEN, ALKYL OF 1 TO 12 CARBON ATOMS SUBSTITUTED WITH 0 OR 4 HALOGEN ATOMS OF ATOMIC NUMBER 9 TO 35, CYCLOALKYL OF 3 TO 12 CARBON ATOMS SUBSTITUTED WITH 0 TO 4 HALOGEN ATOMS OF ATOMIC NUMBER 9 TO 35, ARYL OF 6 TO 12 CARBON ATOMS SUBSTITUTED WITH 0 TO 4 HALOGEN ATOMS OF ATOMIC NUMBER 9 TO 35, NITRO GROUPS OR ALKOXY GROUPS OF 1 TO 6 CARBON ATOMS; R2 IS ALKYL OF 1 TO 10 CARBON ATOMS SUBSTITUTED WITH 0 TO 4 HALOGEN ATOMS OF ATOMIC NUMNBER 17 TO 35, CYCLOALKYL OF 5 TO 10 CARBON ATOMS SUBSTITUTED WITH 0 TO 4 HALOGEN ATOMS OF ATOMIC NUMBER 17 TO 35; AND R3 IS EITHER   -CH&lt;(-CH2-(CH2)N-CH2-CH(-CL)-)   WHEREIN N IS AN INTEGER OF FROM 1 TO 8, OR (B) MONOCHLORONORBORNYL THE COMPOUNDS ARE HERBICIDES.

3,826,644 Patented July 30, 1974 United States PatentOfice 1 3,826,644 r y HERBICIDAL N'-ARYL-N-CHLOROCYCLO- ALKYLTHIO UREAS t. 1 John W. Kobzina, Berkeley, Joseph F. Moore, Richmond, and Gustave K. Kohn, Berkeley, Calif., assignors to Chevron Research Company, San Francisco, Calif. No Drawing. Original application July 14, 1970, Ser. No.

54,855, now Patent No." 3,711,530. Divided and this application Nov. 2, 1972, Ser. No. 303,190 Int. Cl. A0111 9/12 US. CI. 71-98' 12 Claims ABsTRAcroF THE DISCLOSURE Compound of the formula wherein R and R are hydrogen, alkyl of 1 to 12 carbon atoms substituted with or 4 halogen atoms of atomic number 9 to 35,cycloalkyl of 3 to 12 carbon atoms substituted with 0 to 4 halogen atoms of atomic number 9 to 35, aryl of 6 to 12 carbon atoms substituted with 0 to 4 halogen atoms of atomic number 9 to 35, nitro groups or alkoxy groups of 1 to 6 carbon atoms; R is alkyl of 1 to 10 carbon atoms substituted with 0 to 4 halogen atoms of atomic number 17 to 35, cycloalkyl of S to 10 carbon atoms substituted with 0 to 4 halogen atoms of atomic number 17 to 35; and R is either wherein n is an integer of from 1 to 8, or

The compounds are herbicides.

monochloronorbornyl -'This is a division of application Ser. No. 54,855, filed July 14, 1970, now U.S.Pat. 3,711,530.

FIELD OF; THE INVENTION The present-invention is directed to N-substituted-N- chlorocycloalkylthio ureas, their method of preparation and their use as herbicides.

DESCRIPTION OF THE INVENTION wherein R and R (which may be the same or different) are hydrogen, alkyl of 1 to 12 carbonatoms optionally substituted with halogen atoms of atomic number 9 to 35 (fluorine, chlorine or bromine), cycloalkyl of 3 to 12 carbon atoms optionally substituted with halogen atoms of atomic number 9 to 35, aryl of 6 to 12 carbon atoms optionally substituted with halogen atoms of atomic number 9 to 35, nitro groups or alkoxy groups intionally substituted with halogen atoms of atomic number' 17 to-35, preferably 0 to 4 halogen atoms; andR is either a I e -cn-cu,

ol-on-cin wherein n is an integer from 1 to 8, or

R and R are preferably hydrogen, alkyl of 1 to 12, more preferably 1 to 4 carbon atoms substituted with 0 to 4 halogen atoms of atomic number 9 to 35 (i.e., the alkyl may or may not be substituted with halogen atoms; if substituted the number of halogens will be from 1 to 4), cycloalkyl of 3 to 12 carbon atoms substituted with 0 to 4 halogen atoms of atomic number 9 to 35, aryl of 6 to 12 carbon atoms substituted with 0 to 4 halogen atoms of atomic number 9 to 35, nitro groups or alkoxy groups wherein the alkyl portion is from 1 to 6 carbon atoms. Preferably, the total number of substituents on the aromatic nucleus of the aryl radical will not exceed 4.

Still more preferably in the above formula R represents phenyl; phenyl substituted with 1 to 4 halogen atoms of atomic number 9 to35, nitro groups, alkyl groups individually of 1 to 4 carbon atoms or alkoxy groups individually of 1 to 4 carbon atoms, and R is hydrogen or alkyl of 1 to 4 carbon atoms optionally substituted with 0 to 4 halogen atoms of atomic number 9 to 35. Still more preferably R is hydrogen.

R is preferably alkyl of 1 to 6 carbon atoms substituted with 0 to 4 halogen atoms of atomic number 17 to 35, preferably 1 to 2 halogen atoms of atomic number 17 to 35, cycloalkyl of 5 to 6 carbon atoms substituted with 0 to 4 halogenvatoms of atomic number 17 to 35, preferably 1 to 2 halogen atoms of atomic number 17 to 35. Still more preferably R is alkyl of 1 to 4 carbon atoms substituted with 0 to 2 halogen atoms of atomic number 17 to 35, preferably chlorine.

R above as indicated may be either a chlorocycloalkyl group wherein n is an integer offrom 1to 8 and more preferably of from 1 to 4 and still more preferably of from 1 to 2 or a monochloronorbornyl group.

Representative groups which R and R may represent include hydrogen, methyl, ethyl, n-propyl, isopropyl, nbutyl, isobutyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, chloromethyl, bromomethyl, 1,2-dichloroethyl, cyclopropyl, cyclopentyl, cyclohexyl, cyclooctyl, chlorocyclohexyl, fiuorocyclohexyl, phenyl, naphthyl, biphenyl, chlorophenyl, bromophenyl, fiuorophenyl, 2,2-dichlorophenyl, 4-chlorophenyl, Z-fiuoro 4 chlorophenyl, 2-nitrophenyl 2,4-dinitrophenyl, methoxyphenyl, ethoxyphenyl fluoroifaphthyl, chloronaphthyl, etc.

Representative R groups are methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, 2-methylbutyl, S-methylpentyl, chloromethyl, bromomethyl, 1,2-dichloroethyl, cyclopentyl, cyclohexyl, etc.

Representative R groups are 2-chlorocyclopentyl, 2- chlorocyclohexyl, Z-chlorocyclooctyl, 2-chlorocyclododecyl, and monochloronorbornyl.

' Representative compounds of the present invention include:

monochloronor-bornyl N-methyl-N-(Z-chtorocyclopentylthio) urea,

N-methyl-N-(Z-chlbtocyclopentylthio)-N-methyl urea,

N-methyl-'N-(2-chloiiocyclopentylthio) N'-dimethyl urea,

N-methyl-N-(Z-chlorocyclopentylthio)-N'-e thyl-Nrmethyl urea,

. N-methyl-N- (2-chlorocy clopentylthio -N-n-butyl urea,

N-methyl-N-(2-chlorocyclopentylthio)-N'-n-hexyl urea,

2'41 F35; N-methyl N-(il-ehlorocyclop hexyl urea, N-methyl-N-(2-chlorocyclopentylthio)-N-phenyl urea, N-methyl-N'-'(2 chlorocyclopentylthio) N'-naphthyl urea; N-methyl-N- 2-chlorocyc1opentylthio -N-2-fluoromethyl urea, N-methyl-N-(2-chlorocyclopentylthio)-N-2-chlorophenyl urea, N-methyl-N-(2-chlorocyclopentylthio)-N'-3-chlorophenyl urea, N-methyl-N-(2-chlorocyclopentylthio) -N'-4-nitrophenyl urea, N-methyl-N- 2-chlorocyclopentylthi0 -N'-methoxyphenyl urea, N-methyl-N- 2-chlorocyclopentylthio -N'-4-methoxyphenyl-N'-methyl urea, N-methyl-N-(2-chlorocyclohexylthio)-urea, N-methyl-N-( 2-chlorocyclohexylthio -N-methyl urea, N-methyl-N-(2-chlorocyclohexylthio)-N'-phenyl urea, N-methyl-N- 2-chlorocyclohexylthio -N'-2-chlorophenyl urea, N-methyl-N-(2-chlorocyclohexylthio)-N'-4-methoxyphenyl urea, N-ethyl-N- (2-chlorocyclohexylthio) urea, N-ethyl-N-(2-chlorocyclohexylthio)-N'-phenyl urea, N-ethyl-N-(Z-chlorocyclohexylthio)-N'-3-nitrophenyl urea, N-ethyl-N- 2-chlorocyclohexylthio -N-3-nitrophenyl- N-methyl urea, N-butyl-N-(2-chlorocyclohexylthio) urea, N-butyl-N- 2-chlorocyclohexylthio -N'-phenyl urea, N-cyclohexyl-N- (2-chloro cyclohexylthio -N'-phenyl urea, N-chloromethyl-N-(2-chlorocyclohexylthio)-N'-phenyl urea, N-methyl-N- 2-chlorocycloheptylthio -N-phenyl urea, N-niethyl-N-(2chlorocyclooctylthio)-N-phenyl urea, N-methyl-N-(2-chlorocyclononylthio)-N '-phenyl urea, N-mcthyl-N-(2-chlorocyclodecylthio -N-phenyl urea, N-methyl-N- 2-chlorocyc1ododecylthio -N'-phenyl urea, N-rnethyl-N-(monochloronorbornylthio)-N'-phenyl urea, N-methyl-N-(monochloronorbornylthio)-N-2-fiuorophenyl urea, N-methyl-N-(monochloronorbornylthio)-N'-3-chlorophenyl-N-methyl urea, etc.

Compounds of the present invention may be prepared by the following reaction steps 40- 50 Phe pressurea'snot-critical and-"can 136 3111108- pheric or autogenous. The reaction time will generally run from hour to a day or more and more usually in the range from 4 hours to 24 hours.

A solvent will generally b'eiu'sed for the above reaction. I

Benzene is particularly suitable; howeverfothei solvents such as xylene and chlorinated hydrocarbons ,e.g. methyilene" chloride or chloroform can be use d.'Apr6ticisolvents not miscible with water can'also be' .usedand.include. such compounds as. ether, etc. General ly. the solvent will be'present'in-an amount of Y5 to 25 times the volume of reactants.-

For the reactions above; particularly for Step II, a hydrogen halide acceptor is desirable preferably in at least stoichiometric amounts to the I-IC I produced. When the amine is an aromatic amine,itcanbeusedin excess as a basic acceptor for the HCl; however, this is generally not practical. Other halogen halide acceptors are preferred such as triethyl amine or pyridine.

In the above reaction it is generally preferred that stoichiometric amounts of reactants be used. However in Step I the carbamoyl chloride may be present in less than the equimolar amount and in Step II theuamine may be present in excess. However,v it is generally desired that the cyclic or bicyclic reactantof Step I not be in excess of 1 mole per mole of other reactant and that the amine in Step II not be in excessof 2.1 moles per mole of the other reactant. E

Generally any amine chloride formed in the above reaction can be removed by filtrationand excess solvent removed under vacuum. The desired urea product of the present invention can then be purified by chromatography or recrystallization from suitable solvents.

It is difficult to be precise as to the relative positions of the chlorine and sulfur atoms attached to the norbornyl radical. As shown for Step I above, norbornylene is reacted with a carbamoyl chloride to produce the desired carbamate of the present invention. However, due to well-known possible multiple rearrangements under the conditions of the addition reaction of Step I, one of two possible monochloro'norbornyl groups, or'a mixture thereof, is formed. Either 2-chloronorborn-7-yl (2-chlorobicyclo[2.2.l]hept-7-yl) or 3-chloronorborn-2-yl (3-chlorobicyclo[2.2.1]hept-2-yl) or a'mi'xtur'e of the two can be the resulting R group. For --convenience of expres sion, the term monochloronorbornyl is used to"'de scribe either of the two possible structures or their mixture. v H

The carbarnoyl chlorides which are used as reactants in Step I are made by the reaction of isocyanateand SCI;

in accordane with the following reaction;

wherein R is the same as defined above. Thesulfur dichloride/isocyanate molar ratio should be at least 1:1. The sulfur dichloride is preferably present in excess. For best results it is necessary that the sulfur dichloride be in excess of preferably 99%, pure.

The reaction can be accomplished in the presence of a suitable inert organic solvent or neat. Preferably the solventis low boiling and easily removed a low temperature stripping operation. Examples of suitable solvents include: dichloromethane, diethylether, tetrahydrofuran and dimethylfuran.

Sufiicient solvent is used to dissolve the reac'tantsQfIn general it is sufiicient to use about 25 to 200 ml. of solvent for each 0.1 mole isocyanate. Preferably :50 to 100 ml. is used. M

The reaction of the isocyanate and sulfur dichloride is preferably accomplished in the presence of a suitable catalyst, such as for example dibutyl tin dila'urate, tetraethyl ammonium chloride and triethyl' amine. The preferred catalyst is tetraethyla-mmonium chloride. Although the reaction will also proceed without the presence of a catalyst, a catalyst is preferred. Generally about 1% to 60% by weight of catalyst based on isocyanate is sufficient. Preferably the catalyst is removed before isolation of the carbamoyl chloride product or before in situ filtered and the solvent then removed under vacuum. The product after being recrystallized from chloroform-petroleum ether had a melting point of 79-80 C. and had the following chemical analysis: i

reaction with a suitable reactant to produce the herbicidal Calculated Found product described further hereinafter.

Cl ere nt 20. 54 1 .50 The reaction 1s preferably accomplished at a tempera- 9 2g 93 ture of from -50 to 100 C. and at ambient or autoge- P nous pressure. The reactiontime will generally run from 10 i 1; A to 72 hours, more usually /3 to 24 hours. Other urea compounds of the present invention were The carbamoyl chloride product can-be recovered by prepared generally by the methods of Examples 1 and'2 stripping sulfur dichloride and then distilling the desired and are reported in Table I. 'f

TABLE I Element analysis, percent 01 e N Melting point, Cale. Found Cale. Found Cale. Found C.

N -me1:hyl-N-(2'eh1orocyclohexylthio)-N-(2-fiuorophenyl) urea 11. 19 11. 18 10. 12 9. 28 Oil N-methyl-N-(2-ehl0rocyc1ohexylthio) urea 15. 85 15. 70 14. 33 14. 55 12. 52 11. 68 108 N-methyl-N-(2-chlorocyclohexylthio)N'-phenyl urea 11. 86 9. 72 10.35 10. 11 Oil N-methyl-N-(2-ch1orocyclohexylthio)-N',N-di1nethyl urea-. 14. 14 13. 50 12. 78 11.95 Oil N-methyl-N-(2-chlorocyclohexylthio)-N-(4=-methylphenyl) urea 11.33 11.40 10.25 10.03 8.95 8.92 78 N-methyl-N-(2-chloroeyclohexylthio -N-(4-methoxyphenyl) ur 10.78 10. 42 9. 75 9. 81 8. 52 8.42 71-73 N-n-butyl-N(2-ehlorocyclohexylthio)-N-(4-ehloropheny1) urea"... 8.50 8.87 18. 90 19 55 7. 50 6. 12 Oil N-methyl-N-(2ch1orocyclopenty1thio)-N-(4-ehlorophenyl) urea 22. 21 22. 10. 04 9. 93 8. 77 8. 34 49 N-methyl-N-(monochloronorbornylthio) urea 15. 10 15. 00 13. 6s 13. 35 11. e4 11. 28 128-131 N-methyl-N-(monochloronorbornylthio)-N-(4-methylpheuyl) urea 10. 91 8. 93 9. 87 9. 42 8. 62 8. 38 59-61 N-methyl-N-(mononhloronorbornylthio)-N-phenyl urea 10.59 9. 75 9.58 10 16 Oil product from the mixture. When the catalyst is insoluble, UTILITY the carbamoyl chloride product can be recovered by stripping sulfur dichloride, filtering the insoluble catalyst and then evaporating off the low boiling solvent.

The present invention can be more usually understood by reference to the following examples.

EXAMPLES Example 1 Preparation of N-methyl-N-(2-chlorocyclohexylthio)- N'-(4-chlorophenyl) urea.- ml. of N-methyl-N-chlorothio carbamoyl chloride was added to 33 ml. of cyclohexene and cooled in ice. The reaction mixture was stirred several hours, then the excess cyclohexene removed under vacuum. The resultant carbamoyl chloride product was diluted with ml. of benzene, then 8 g. of 4-chloroaniline and105 ml. of benzene were added and the reaction mixture stirred overnight at room temperature. Following removal of the aniline hydrochloride by filtration, the filtrate was washed with ml. of 10% hydrochloric acid and then with 25 ml. of water. The washed solution of product was dried over magnesium sulfate and the solvent removed under vacuum. The crude product was chromatographed on silica gel, eluting with varying mixtures of petroleum ether and diethyl ether. The

isolated product was a white crystalline solid, had a melting point of 80 to 82 C. and showed the following chemical analysis:

Preparation of N-methyl N (monochloronorbornylthio)-N'-(4-chlorophenyl) urea.--20 g. of N-methyl-N- chlorothio carbamoyl chloride was added at 0 C. to 12 g. of 2,3-bicyclo[2.2.1Jheptene (norbornylene) in 50 ml. of benzene and the reaction mixture stirred for 1 /2 hours at 0 C. 32 g. of 4-chloroani1ine and 150 ml. of benzene was then added dropwise and the mixture stirred for 20 hours at room temperature. The aniline-hydrochloride precipitate was removed by filtration and the filtrate washed twice with 50 ml. portions of 5% hydrochloric acid and then once with 50 ml. of water. The washed solution of product was dried over magnesium sulfate and The ureas of the present invention are, in general, herbicidal in both preand post-emergence applications. For pre-emergence control of undesirable vegetation these ureas will be applied in herbicidal quantities to the environment, e.g., soil infested with seeds and/or seedlings of such vegetation. Such application will inhibit the growth of or kill the seeds, germinating seeds and seedlings. For post-emergence applications the ureas of the present invention will be applied directly to the foliage and other plant parts. Generally they are effective against weed grasses as well as broadleaved weeds. Some may be selective with respect to type of application and/or type of weed.

Preand post-emergence herbicidal tests on representative ureas of this invention were made using the following methods:

Pre-Emergence Test An acetone solution of the test ureas was prepared by mixing 750 mg. urea, 220 mg. of a nonionic surfactant and 5 ml. of acetone. This solution was added to approximately 125 ml. of water containing 156 mg. of surfactant.

Seeds of the test vegetation were planted in a pot of soil and the urea solution was sprayed uniformly onto the soil surface at a dose of mg. per cmfi. The pot was watered and placed in a greenhouse. The pot was watered intermittently and was observed for seedling emergence, health of emerging seedlings, etc. for a 3-week period. At the end of this period the herbicidal eifectiveness of the urea was ratedibased on the physiological observations. A 0 to 100 scale was used; 0 representing no' phytotoxicity, 100 representing complete kill.

Post-Emergence Test dried, they were placed in a greenhouse and then watered intermittently at their bases are needed. The plants were observed periodically for phytotoxic effects and physiological and morphological responses to the treatment. After 3 weeks the herbicidal effectiveness of the urea was rated fbased on these observations. A to 100 scale was (a) used; .0 representing no phytotoxicity, 100 representing CH complete kill. v

The results of these tests appear in Table II. C1"CH CH1 r TABLE II Herbicidalefiectiveness,pro/post Compound v 0 w o M P L N-methyl-N-(2-chlorocyclohexylthi0)-N-(4-ch10r0phenyl) urea 98/100 100/100 99/100 100/100 100/ 100 100/100 N-methyl-N (2ch10rocyclohexylth1o)-Nt-(2-fluorophenyl) urea* 100/100 98/95 99/83 98/100 100/100 95/100 N-methyl-N-(z chlorocyclohexylthio) urea 35/- /20 N-methy1-N=(Z-chlorocyclohexylthlo)-N' phenyl urea 100/93 100/85 100/79 100/ 100 v 100/ 100 100/ 100 N-rnethyl-N-(Z-chlorocyclohexylthio)N,N-dimethyl urea... 20 65/- 65/ -/40 ,/20 N-methyl-N-(2'chlorocyclohexy1thi0)-N-(4-methylphenyl) urea 100/85 100/70 100/30 100/95 100/100 100/100 N-methyl-N-(2-chlorocyelol1exylthio)-N'-(4-methoxyphenyl) urea 96/35 98/26 100/ 100/85 100/90 100/90 N-n-butyl-N-(Z-chlorocyclohexylthio)-N(4-chlorophenyl) urea 30/95 /95 100 67/- 37/100 67/100 N-methyl-N-(2-chlorocyc1opentylthio)-N-(4-chlorophenyl) urea 100/100 100/100 100/100 100/100 100/100 100/100 N-rnethyl- (monochloronorbornylthio)-N-(4chlor0pheny1) ure 50/10 97/100 97/100 100/- 100/100 100/100 N-methyl-N-(monochloronorbornylthio) urea 37/ 27/- 30/ 57/- 43/- N -methyl-N -(monochloronorb0rny1thio)-N'-(4-mcthylpheny1) urea... 33/100 33/100 100/100 98/100 100/10 100/100 N-methyl-N-(monochloronorbornylthio)-N-phenyl urea 100/83 98/- 100/ 100/98 100/70 96/100 33 micrograms/cm. application.

Norm-O =Wild Oats (Avma fatua); W=Watergrass (Echinochlqa crusgalli); C=Crabgrass (Digitaria aanguz'nalis); M=Mustard (Brassica arve'nsis); P=Pigweed (Amaranthus reiroflezus); L=Lambsquarter (Chmopodmm album). I I

The amount of urea administered will vary with the particular plant part or plant growth medium which is to be contacted, the general location of application, i.e., sheltered areas such as greenhouses as compared to exposed areas such as fields, as well as the desired type of control. For pre-emergent control of most plants dosages in the range of about 0.5 to 20 lbs. per acre will be used. Such administration will give a concentration of about 2 to 80 p.p.m. urea distributed throughout 0.1 acre-foot. For post-emergence application, such as foliar spray application, compositions containing about 0.5 to 8 lbs. urea per 100 gal. spray will be used. Such application is equivalent to about 0.5 to 20 lbs. urea per acre.

The herbicidal compositions of this invention comprise a herbicidal amount of one or more of the above described ureas intimately admixed with a biologically inert carrier. The carrier may be a liquid diluent such as water or acetone or a solid. The solid may be in the form of dust powder or granules. These compositions will also usually contain adjuvants such as a wetting or dispersing agent to facilitate their penetration into the plant growth media or plant tissue and generally enhance their efiectiveness. These compositions may also contain other pesticides, stabilizers, conditioners, fillers and the like.

As will be evident to those skilled in the art, various modifications on this invention can be made or followed, in the light of the foregoing disclosure and discussion, without departing from the spirit or scope of the disclosure or from the scope of the following claims.

We claim: 1. Herbicidal composition comprising a biologically inert carrier and an herbicidally effective amount of a compound of the formula K i f" N:-C-N 1 s-m wherein R is phenyl, 'phenyl"substituted with 1 to 4 halogen atoms of atomic number 9 to 35, nitro groups or alkyl groups individually of 1 to 4 carbon atoms, alkoxy groups'individually having 1 106 carbon atoms, R is hydrogen or alkyl of 1 to14 carbon atoms; R is alkylof 1 to 4 carbon atoms and R is either wherein n is an integer of from 1 to 4, or (b) monochloronorbornyl, selected from 2-chloronorborn-7-yl, 3- chloronorborn-Z-yl or a mixture thereof.

2. Composition of Claim 1 wherein R is phenyl substituted with 1 to 4 halogen atoms of atomic number 9 to 35 or alkyl groups of 1 to 4 carbon atoms.

3. Composition of Claim 2 wherein R is hydrogen, R is methyl and R is 2-chlorocyclohexyl or 2-chlorocycl0- pentyl.

4. Composition of Claim 3 wherein R is 4-chlorophenyl.

5. Composition of Claim 3 wherein R is 2-fluorophenyl.

6. Method for controlling the growth of undesirable vegetation which comprises applying to the vegetation or the growth media of the vegetation a herbicidally effective amount of the compound of Claim 1.

7. Method of Claim 6 wherein R is phenyl substituted with 1 to 4 halogen atoms of atomic number 9 to 35 or alkyl groups of 1 to 4 carbon atoms.

8. Method of Claim 7 wherein R is hydrogen, R is methyl and R is 2-chlorocyclohexyl or 2-chlorocyclopentyl.

9. Method of Claim 8 wherein R is4-chlorophenyl.

10. Method of Claim 8 wherein R is 2-fluorophenyl.

11. Composition of Claim 5 wherein R is Z-chlorocyclohexyl.

12. Method of Claim 10 wherein R is 2-chlorocyclohexyl.

References Cited UNITED STATES PATENTS 3,699,163 10/1972 Kohn 71-120 3,697,572 10/1972 Brown 260-453 R 2,868,633 1/1959 Goodhue 71-98 3,142,554 7/1964 Godfrey 71-98 3,001,861 9/1961 Fischer et a1. 71-119 3,496,208 2/1970 Bachman et al 260-453 R 3,502,705 3/1970 Brown 260-453 R 3,234,275 2/1966 Malz et al 71-98 3,344,153 9/1967 Kuhle et a1. 260-453 R 3,347,658 10/1967 Luckenbaugh 71-119 3,351,457 11/1967 .Luckenbaugh 71-120 3,352,662 11/1967 Klopping et al. 71-120 3,124,447 3/1964 Wineman et al. .4. 71-103 3,652,630 3/1972 Brown 71-67 GLENNQN H. HOLLRAH, Primary Examiner 

